Key-locking device for pneumatic pianos.



PATBNTED AUG. 1, 1905.

J. GARRUTHERS. KEY LOCKING DEVICE FOR PNEUMATIC PIANOS.

APPLICATION FILED DEO. 15l 1904.

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UNITED STATES PATENT OFFICE.

JAMES OARRUTHERS, OF GARWOOD, NEW JERSEY, ASSIGNOR TO THE AUTOPIANO CO., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

KEY-LOCKING DEVICE FOR PNEUMATIC PIANOS.

Specification of Letters Patent.

Patented Aug. 1, 1905'.

Application filed December l5, 1904. Serial No. 236,917.

To @ZZ whom it may concern.'

Be it known that I, JAMEs OARRUTHERS, a citizen of Great Britain, residing at Garwood, Union county, State of New Jersey, have invented new and useful Improvements in Key- Locking Devices for Pneumatic Pianos, of which the following is a specification.

This invention relates to an improvement in pneumatic pianos of that class which can be played by hand as well as by a perforated musicsheet and in which the automatic playing mechanism acts directly upon the action and not through the intervention of the keys. With this class of pianos it is necessary that the keys be locked against movement when the piano is to be played mechanically, so as to prevent rattling.

My invention provides improved means for effecting this locking of the keys without eX- tra manipulation and in a reliable manner.

In the accompanying drawings, Figure 1 is a vertical section, partly in elevation, of my improved locking device, showing the keys unlocked; Fig. 2, a similar view showing the keys locked; and Fig. 3, a rear View, partly in section, of Fig. 1.

The letter c represents the key-bottom of a piano of the class described, while?) represents the keys adapted to actuate the abstracts c of the action by pilots When the instrument is played by mechanical means, the latter operate directly upon the abstracts and not through the intervention of the key. In order to lock the latter against rattling when the piano is thus played mechanically, I have. devised the following construction: Across the rear ends of keys extends a vertically-movable locking-bar d, which may be either lowered upon the keys or raised off the same. The bar d is perforated vertically, as at d', for the reception of guide-pins e, thatare attached to the key-bottom a at c. From the bar CZ depends, near each end thereof, a lifter f, that extends back of the keys and when lowered projects slightly above the key-bottom c, Fig. 2. The lower end of each lifter f is adapted to be operatively engaged by a horizontallymovable slide g, having a beveled rear edge. The slides are tted upon the threaded rear ends of rods g', the front ends of which are bent and are pivoted at g2 to the key-slip 7L.

This key-slip is hinged at L to the key-bottom a and covers or exposes the stops fi, which are used when the piano is played mechanically.

When the piano is played by means of the keys I), the key-slip is raised to cover stops This closing of the key-slip will, by rods g', push the slides g backward to engage lifters f and raise bar d ofi' keys b, Fig. 1. Thus the keys may be freely manipulated. If the piano is to be played mechanically, the keyslip is turned down to expose stops il and draw slides g forward and out of engagement with lifters f. The supports for the bar OZ being thus withdrawn, the latter will descend by gravity upon keys b and lock the same against movement, Fig. 2. It will thus be seen that by turning the key-slip the keys are automatically locked or unlocked without requiring any separate manipulation of the locking mechanism.

What I claim is- .1. In a' key-locking device for pneumatic pianos, the combination of a key with a locking-bar adapted to engage the same, a hinged key-slip, and means for operatively connecting said bar to said key-slip, substantially as specified. i

2. In a key-locking device for pneumatic pianos, the combination of a key with a vertically-movablelocking-bar adapted to engage the same, lifters depending from the bar, slides adapted to engage the lifters, and a hinged key-slip to which the slides are operatively connected, substantially as specified.

3. In a key-locking device for pneumatic pianos, the combination of a key with a Vertically-movable locking-bar adapted to engage the same, means for guiding said bar, lifters depending from the bar, beveled slides adapted to engage the lifters, and a hinged keyslip to which the slides are operatively connected, substantially as specified.

Signed by me at New York city, (Manhattan,) New York, this 14th day of December, 1904.

JAMES CARRUTHERS.

Witnesses:

WILLIAM SCHULZ, FRANK v. BRinsnN. 

